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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

850 results found.

  1. MAXI GRB220607.41: Global MASTER-Net observations report
  2. Konus-Wind detection of GRB 220506A
  3. Konus-Wind detection of GRB 220514B
  4. GRB 220514B: Swift-XRT observations
  5. GRB 220514B: Tiled Swift observations
  6. GRB 220514B: MAXI/GSC detection
  7. MAXI GRB220514.98: Global MASTER-Net observations report
  8. GRB 220506A: MITSuME Akeno optical upper limits
  9. GRB 220506A: GIT optical upper limit.
  10. GRB 220506A: BOOTES-5/JGT optical upper limit
  11. GRB 220506A: Swift-XRT afterglow detection
  12. GRB 220506A: Tiled Swift observations
  13. GRB 220506A/MAXI J1558-266: MAXI/GSC detection
  14. MAXI GRB220506.27: Global MASTER-Net observations report
  15. GRB 220411A: AstroSat CZTI detection
  16. Fermi GRB 220411A: Global MASTER-Net observations report
  17. GRB 220310A: MITSuME Akeno optical observation
  18. IPN triangulation of GRB 220310A
  19. GRB 220310A: [KAO-Egypt] SDSS r, i observation
  20. Konus-Wind detection of GRB 220310A
  21. GRB 220310A: GIT confirmation of optical afterglow.
  22. GRB 220310A: MASTER optical counterpart detection
  23. GRB 220310A: Swift ToO observations
  24. GRB 220310A: CALET Gamma-Ray Burst Monitor detection
  25. GRB 220310A: MAXI/GSC detection
  26. MAXI GRB220310.02: Global MASTER-Net observations report
  27. GRB 211227A: Konus-Wind detection and joint Konus-Wind+Swift-BAT spectral analysis
  28. GRB 211227A: Deep early CAHA 2.2m/CAFOS observation
  29. GRB 211227A: CALET Gamma-Ray Burst Monitor detection
  30. GRB 211227A: MAXI/GSC detection
  31. GRB 211225A: MITSuME Akeno optical upper limits
  32. MAXI GRB211225.14: Global MASTER-Net observations report
  33. GRB 211225A/MAXI J0827-071: MAXI/GSC detection
  34. GRB 211218A: MITSuME Akeno optical upper limits
  35. GRB 211218A, MAXI J0909-041: MAXI/GSC detection
  36. MAXI GRB211218.04: Global MASTER-Net observations report
  37. Fermi GRB 211211B: Global MASTER-Net observations report
  38. GRB 211115A: CALET Gamma-Ray Burst Monitor detection
  39. GRB 211115A: MAXI/GSC detection
  40. GRB 210822A: Swift/UVOT Detection
  41. MAXI GRB210709.93: Global MASTER-Net observations report
  42. Swift-BAT Trigger 1055000/GRB210612.54: MASTER optical source observation
  43. GRB 210607A/MAXI J1733-222: MAXI/GSC detection
  44. MAXI GRB210607.82: Global MASTER-Net observations report
  45. Konus-Wind detection of GRB 210602A
  46. MAXI GRB210602.50: Global MASTER-Net observations report
  47. GRB 210602A: CALET Gamma-Ray Burst Monitor detection
  48. GRB 210602A: MAXI/GSC detection
  49. GRB 210528B: DDOTI Upper Limits on the Afterglow
  50. MAXI GRB210528.95: Global MASTER-Net observations report
  51. GRB 210528B: MAXI/GSC detection
  52. MAXI GRB210521.54: Global MASTER-Net observations report
  53. GRB 210521A: MAXI/GSC detection
  54. Swift Detection of MAXI J1803-298 including an optical counterpart
  55. MAXI GRB210501.83: Global MASTER-Net observations report
  56. MAXI GRB210320.89: Global MASTER-Net observations report
  57. GRB 210320A: MAXI/GSC detection
  58. GRB 210305A: Swift/UVOT Upper Limits
  59. Konus-Wind detection of GRB 210222A
  60. GRB 210222A: CALET Gamma-Ray Burst Monitor detection
  61. GRB 210222A: MAXI/GSC detection
  62. GRB 210210A: Swift/UVOT Detection
  63. SGR 1935+2154: MAXI/GSC detection
  64. NuEm-210111A: MAXI/GSC upper limit
  65. MAXI GRB210110.64: Global MASTER-Net observations report
  66. GRB 210110A: MAXI/GSC detection
  67. GRB 210109A: MAXI/GSC detection
  68. GRB 210102B: further Swift-XRT observations
  69. GRB 210102B: Assy optical afterglow identification
  70. GRB 210102B: Tiled Swift observations
  71. GRB 210102B: Assy optical observations
  72. GRB 210102B: Swift-XRT observations
  73. MAXI GRB210102.38: Global MASTER-Net observations report
  74. GRB 210102B: Tiled Swift observations
  75. GRB 210102B: MAXI/GSC detection
  76. IceCube-201209A : MAXI/GSC upper limit
  77. MAXI GRB201021.68: Global MASTER-Net observations report
  78. GRB 201021B MAXI/GSC detection
  79. GRB 200903D: MAXI/GSC detection
  80. GRB 200809B: Fermi GBM detection
  81. GRB 200809B: Swift-XRT afterglow detection
  82. GRB 200809B: MAXI/GSC detection
  83. GRB 200615B: CALET Gamma-Ray Burst Monitor detection
  84. GRB 200615B: MAXI/GSC detection
  85. Fermi GRB 200524A: Global MASTER-Net observations report
  86. GRB 200517A: Swift-XRT Confirmation of afterglow
  87. Fermi GBM Sub-Threshold Detection of GRB 200517A
  88. GRB 200517A: Swift-XRT afterglow detection
  89. GRB 200514A: AstroSat CZTI detection
  90. GRB 200517A: Tiled Swift observations
  91. GRB 200517A: MAXI/GSC detection
  92. GRB 200514A: MITSuME Akeno optical upper limits
  93. GRB 200514A: CALET Gamma-Ray Burst Monitor detection
  94. GRB 200514A: MAXI/GSC detection
  95. Konus-Wind observation of a very intense bursting activity of SGR 1935+2154
  96. SGR 1935+2154: MAXI/GSC detection
  97. GRB 200320B: MAXI/GSC detection
  98. LIGO/Virgo S200316bj: Coverage and upper limits from MAXI/GSC observations
  99. LIGO/Virgo S200311bg: Coverage and upper limits from MAXI/GSC observations
  100. GRB 200310A: MAXI/GSC detection

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